In post-MI patients undergoing VT ablation, endocardial bipolar dense scar area >22.5 cm2 predicted scar transmurality, and late potential abolition (achieved in 51%) reduced VT recurrence.
Cohort (n=100)
Do electroanatomical mapping characteristics predict scar transmurality and clinical outcomes in postmyocardial infarction patients undergoing VT ablation?
Endocardial scar extension and density predict scar transmurality and the presence of late potentials, and successful abolition of late potentials improves outcomes in post-MI patients undergoing VT ablation.
BACKGROUND: Catheter ablation is an important therapeutic option in postmyocardial infarction patients with ventricular tachycardia (VT). We analyzed the endo-epicardial electroanatomical mapping (EAM) voltage and morphology characteristics, their association with clinical data and their prognostic value in a large cohort of postmyocardial infarction patients. METHODS AND RESULTS: We performed total and segmental analysis of voltage (bipolar dense scar DS and low voltage areas, unipolar low voltage and penumbra areas) and morphology characteristics (presence of abnormal late potentials LPs and early potentials EPs) in 100 postmyocardial infarction patients undergoing electroanatomical mapping-based VT ablation (26 endo-epicardial procedures) from 2010-2012. All patients had unipolar low voltage areas, whereas 18% had no identifiable endocardial bipolar DS areas. Endocardial bipolar DS area >22.5 cm(2) best predicted scar transmurality. Endo-epicardial LPs were recorded in 2/3 patients, more frequently in nonseptal myocardial segments and were abolished in 51%. Endocardial bipolar DS area >7 cm(2) and endocardial bipolar scar density >0.35 predicted epicardial LPs. Isolated LPs are located mainly epicardially and EPs endocardially. As a primary strategy, LPs and VT-mapping ablation occurred in 48%, only VT-mapping ablation in 27%, only LPs ablation in 17%, and EPs ablation in 6%. Endocardial LP abolition was associated with reduced VT recurrence and increased unipolar penumbra area predicted cardiac death. CONCLUSIONS: Endocardial scar extension and density predict scar transmurality and endo-epicardial presence of LPs, although DS is not always identified in postmyocardial infarction patients. LPs, most frequently located in nonseptal myocardial segments, were abolished in 51% resulting in improved outcome.
Tsiachris et al. (Fri,) conducted a cohort in Postmyocardial infarction with ventricular tachycardia (n=100). Electroanatomical mapping-based VT ablation was evaluated on Prognostic value of endo-epicardial electroanatomical mapping characteristics. In post-MI patients undergoing VT ablation, endocardial bipolar dense scar area >22.5 cm2 predicted scar transmurality, and late potential abolition (achieved in 51%) reduced VT recurrence.